With every extra layer that's been added to baseball's postseason, the difference between the six-month regular season and October has become more pronounced. A good team is a good team, sure, but the playoff crucible tests different facets of a team in different ways than does the season-long grind.

The regular season challenges a 25-man roster. Teams with holes at the back of the starting rotation, or in middle relief, for example, will pay for those flaws over the course of the summer. In October, the effective roster gets much smaller. A fifth starter scarcely matters, and even a shaky No. 4 can be papered over. It's more important to have three or four great relievers than six or seven good ones. Defense becomes magnified, as well.

Offenses takes on a different look, too. It's more important to be able to hit the ball out of the park in October; teams that require multiple baserunners to score are at a disadvantage against the top pitching staffs and defenses.

Even managing is a different art. A great deal of managing in the regular season is handling personalities. In the playoffs, tactical acumen becomes a bigger part of the equation, and poor tacticians are often exposed.

And there's one last key: to win over six months, you have to be good over most of those six months. In October, what matters is what you do now. Many teams are not the same at year's end as they were at the beginning. It's always wise to look at what a team is actually going to battle with, rather than what got it to that point. They're not always the same.

What it all means is that teams that limp into October, teams that barely make the postseason, can be especially dangerous once they get in. And some clubs that put up big win totals over 162 games can be vulnerable in a best-of-five or best-of-seven series. Look at last season's Cardinals, who rode a powerful lineup, an improved defense and an impressive bullpen to a World Series title.

As the postseason approaches -- it's a little more than three weeks away -- here's a look at some of the teams that could be serious handfuls if they make it into the playoffs. We're leaving out teams like the Nationals and Rangers. Anybody can pick the favorites. This is more about identifying teams that are more dangerous than they may appear.

Baltimore Orioles: Sure, they're a long shot. They're far from a guarantee even to make it into October. But if they do, there are some intriguing reasons to think it could work out surprisingly well with the right matchup.

First and foremost is the one way this team really recalls last year's Cardinals: the combination of an effective bullpen and a manager who is a master at manipulating it. Buck Showalter has been brilliant in deploying his relievers all season. And one of the best things he's done is to keep them fresh, so that he'll still have plenty to draw on down the stretch.

Additionally, the Orioles' primary offensive talent is hitting the ball out of the park, especially at home. They're not good enough at getting on base, and their rotation is filled with questions. So it's not as though the O's will be a favorite if they get in. But they'll be more dangerous than a lot of people will probably think they are.

Atlanta Braves: The back of the Braves' bullpen is absolutely dominant, and that's a very good place to start. The Atlanta rotation has a significant number of questions, but if they can be good enough, they can hand the ball over to a ferocious relief corps. It's unclear whether that bullpen has the kind of skillful hand guiding it that the Orioles or last year's Cardinals had, but having the weapons is a good place to start.

The Braves aren't a great defensive team, but they're better than they've been in a while, thanks to the return of shortstop Andrelton Simmons. The rookie makes them a much better team, and he is one of the reasons to think Atlanta could be sneaky good in the postseason.

Then there's the offense, which is quite deep and potent. Atlanta has danger at just about every spot in the batting order, which is another excellent way to keep from getting shut down in October. A lineup that's reliant on a couple of bashers can be exposed much more easily than one with bopper after bopper.

Los Angeles Angels: The Angels fall short in one critical area: their bullpen, while less troublesome than it was earlier in the year, is still not up to the usual Angels standard. Even so, it's very easy to see how things could come together for this team in a month of postseason baseball.

The manager, of course, has been here before and is a solid tactician. Mike Scioscia's lineup is as good as any in either league. The Angels are one of the best defensive teams in baseball.

Their problem, throughout the regular season, has been the starting rotation. And that's just odd for a team that was supposed to be built around its starting five. Danny Haren, Ervin Santana and Zack Greinke have not pitched up to expectations, and Jered Weaver has been hurt.

But seriously now ... are you going to write those guys off? They're already getting hot. There's so much talent in their rotation that it doesn't take much squinting at all to see them putting together a run of dominant starting pitching all the way through October.